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Zhang W, Luo H, Li F, Zhang B, Zhao Y, Feng N, Liu Y. Electrooxidation of Formamidine Disulfide Simultaneously Investigated by On-Line High Performance Liquid Chromatography and Cyclic Voltammetry. ChemistryOpen 2021; 10:1074-1080. [PMID: 34676686 PMCID: PMC8532009 DOI: 10.1002/open.202100197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 10/05/2021] [Indexed: 11/10/2022] Open
Abstract
The electro-oxidation of formamidine disulfide, an important sulfur-containing compound, was simultaneously investigated with on-line high-performance liquid chromatography and cyclic voltammetry. Using a home-made microporous sampler located at the electrode interface, the solution on the electrode surface was in situ sampled and analyzed. The electrochemical scanning was synchronously performed, which allowed the electro-oxidation products to be detected at a given potential. The main products on the surface of platinum electrode were found to be thiourea, formamidine sulfinic acid, cyanamide, and elemental sulfur. Forced convection arising from the sampling played an important role in the electrochemical oxidation. The extraction of electrode surface solution promoted the renewal of reactant and its intermediates, which induced the change of cyclic voltammetry curve. The forced convection also contributed to the redox peak current of the species on the cyclic voltammetry curves through the change of concentration of reactant and its intermediates. This technique can help to explore the reaction mechanism of complex electrochemical reactions.
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Affiliation(s)
- Wei Zhang
- College of ChemistryChemical Engineering and Materials ScienceZaozhuang UniversityZaozhuangChina
| | - Hainan Luo
- College of ChemistryChemical Engineering and Materials ScienceZaozhuang UniversityZaozhuangChina
| | - Fengli Li
- College of ChemistryChemical Engineering and Materials ScienceZaozhuang UniversityZaozhuangChina
| | - Baoying Zhang
- College of ChemistryChemical Engineering and Materials ScienceZaozhuang UniversityZaozhuangChina
| | - Yuyan Zhao
- College of ChemistryChemical Engineering and Materials ScienceZaozhuang UniversityZaozhuangChina
| | - Na Feng
- College of Chemical EngineeringYangzhou Polytechnic InstituteYangzhouChina
| | - Yang Liu
- College of ChemistryChemical Engineering and Materials ScienceZaozhuang UniversityZaozhuangChina
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Shabik MF, Begum H, Rahman MM, Marwani HM, Hasnat MA. Heterogeneous Kinetics of Thiourea Electro-Catalytic Oxidation Reactions on Palladium Surface in Aqueous Medium. Chem Asian J 2020; 15:4327-4338. [PMID: 33140908 DOI: 10.1002/asia.202001016] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 10/28/2020] [Indexed: 11/10/2022]
Abstract
The electrochemical behaviors of thiourea (TU) oxidation have been studied at Palladium (Pd) electrode in the acidic medium by recording cyclic voltammograms (CVs). The influence of pH was investigated in the pH range of 1.0 to 9.0. Facilitated adsorption of TU on electrode surface results in enhanced catalytic response in acidic medium and maximum electro-catalytic response was found at pH∼3.0. Chronoamperometric (CA) experiment determined this oxidation as 1e- transfer process and the variation of TU concentration reveals a 1st order kinetics. In the CV responses, the large value of peak separation (▵Ep >380 mV) calculated by the variation of scan rate indicates that oxidation of TU is an irreversible process. With the aid of convolution potential sweep voltammetry (CPSV), the standard rate constant (k°) for the reaction was found to be 7.1×10-4 cm/s and the formal potential constant (E°' ) was evaluated to be ∼0.37 V vs Ag/AgCl (sat. KCl). The value of transfer coefficient (α) was found to vary from 0.74 to 0.40 with applied potential (E). From the potential dependent variation of transfer coefficient (α) and activation energy (▵G≠ ), it was concluded that the overall electrochemical oxidation of TU follows a stepwise mechanism at lower potential (<0.40) V and a concerted one at relatively higher potential (>0.40) V. The FTIR analysis of the product after oxidation of TU molecules confirmed the appearance of a new sharp band near 530 cm-1 due to the formation of S-S bonds suggesting formation of formamidine disulfide (FD) ions.
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Affiliation(s)
- Md Fazle Shabik
- Department of Chemistry, School of Physical Sciences, Shahjalal University of Science and Technology, Sylhet, 3100, Bangladesh
| | - Humayra Begum
- Department of Chemistry, School of Physical Sciences, Shahjalal University of Science and Technology, Sylhet, 3100, Bangladesh
| | - Mohammed M Rahman
- Department of Chemistry, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
| | - Hadi M Marwani
- Department of Chemistry, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
| | - Mohammad A Hasnat
- Department of Chemistry, School of Physical Sciences, Shahjalal University of Science and Technology, Sylhet, 3100, Bangladesh.,Bangladesh Academy of Sciences, Agargoan, Dhaka, 1207, Bangladesh
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Cheuquepán W, Orts JM, Rodes A. On the electrochemical behavior of formamidine disulfide on gold electrodes in acid media. J Electroanal Chem (Lausanne) 2016. [DOI: 10.1016/j.jelechem.2016.01.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Zelinsky A, Pirogov B. Numerical simulation and experiment in the systems of labile complexes of metals. Silver reduction from the thiourea electrolyte. J Electroanal Chem (Lausanne) 2013. [DOI: 10.1016/j.jelechem.2013.01.041] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Adsorption and electro-oxidation of N-alkyl and N,N’-dialkyl thioureas on gold electrodes in acid solutions. A combined FTIRRAS and voltammetry study. J Solid State Electrochem 2007. [DOI: 10.1007/s10008-007-0447-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Using an electrode with renewable surface for study of silver reduction from acid thiourea solutions. J APPL ELECTROCHEM 2007. [DOI: 10.1007/s10800-007-9434-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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The irreversible characteristic analysis of thiourea on copper electrodes in aqueous 0.5mol/L sulphuric acid. Electrochem commun 2007. [DOI: 10.1016/j.elecom.2007.06.025] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Adsorption and oxidation pathways of thiourea at polycrystalline platinum electrodes. J Electroanal Chem (Lausanne) 2006. [DOI: 10.1016/j.jelechem.2005.12.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Larsen AG, Johannsen K, Gothelf KV. An electrochemical quartz crystal microbalance study of the etching of gold surfaces in the presence of tetramethylthiourea. J Colloid Interface Sci 2004; 279:158-66. [PMID: 15380425 DOI: 10.1016/j.jcis.2004.06.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2004] [Accepted: 06/01/2004] [Indexed: 10/26/2022]
Abstract
The oxidation of tetramethylthiourea (TMTU) at gold electrodes in acetonitrile, leading to dissolution of the electrode, has been studied by electrochemical methods and by an electrochemical quartz crystal microbalance (EQCM). TMTU in acetonitrile readily adsorbs at gold electrodes and an estimated coverage of 5.5 x 10(-10) mol cm(-2) (30 A2 per molecule) was measured electrochemically. Nevertheless, the oxidation of TMTU in solution is a diffusion-controlled process and is strongly influenced by the electrode material, as observed by comparison of gold electrodes with glassy carbon and platinum working electrodes. In the absence of TMTU, EQCM cyclic voltammetry experiments showed dissolution of gold through a 1e- oxidation process at potentials more positive than 1.20 V vs saturated calomel electrode (SCE). Potential step and cyclic voltammetry EQCM experiments performed using gold surfaces in the presence of TMTU revealed TMTU-assisted etching of gold at potentials as low as 0.35 V vs SCE. In the potential region from 0.35 to 1.20 V the current response of TMTU oxidation mimics the response expected for a redox-active species in solution, including the presence of a mass-transfer-limited region, which supports the conclusion that the etching process in this potential region is initiated by the oxidation of TMTU at the gold surface. The current efficiency of the TMTU-assisted etching was found to vary between 12 electrons per gold atom dissolved (e/Au) (E = 0.50 V vs SCE) and 2 e/Au (0.90 V < E < 1.20 V). At potentials <0.90 V the dominant electrochemical process is the formation of TMTU+, whereas at higher potentials the etching of the gold surface by formation of a Au(I)-TMTU+ species becomes equally important. At potentials above 1.20 V the etching is no longer dependent on the diffusion of TMTU and the e/Au value approaches 1.
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Affiliation(s)
- Allan Godsk Larsen
- Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 C, Denmark
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García G, Rodríguez JL, Lacconi GI, Pastor E. Spectroscopic investigation of the adsorption and oxidation of thiourea on polycrystalline Au and Au(111) in acidic media. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:8773-8780. [PMID: 15379505 DOI: 10.1021/la048978n] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
In the present paper, a systematic electrochemical investigation on thiourea (TU) electrooxidation was developed on polycrystalline and (111) single-crystal gold electrodes in 0.1 M perchloric acid. The combination of cyclic voltammetry with in situ Fourier transform infrared spectroscopy (FTIRS) and differential electrochemical mass spectrometry techniques have allowed the nature of the species formed during the electroadsorption and electrooxidation of TU to be established. FTIRS experiments were performed in D2O to clean up the region of the H2O bending around 1600 cm(-1). It was concluded that TU adsorbs tilted on the surface in the 0.05-0.40 VRHE potential range. A dual-path reaction mechanism was evidenced in the oxidation process. The first pathway takes place from adsorbed TU at E > 0.40 VRHE and implies the formation of [Au(I)-(TU)2]+, which is oxidized to NH2CN and S0 at E > 0.80 VRHE. In a following oxidation step at E > 1.20 V, N2, CO2, and HSO4-/SO4(2-) were produced. The second parallel reaction occurs from TU in solution at E > 0.50 VRHE to form (TU)2(2+). All these species were characterized from the spectroscopic experiments. Similar results were obtained for both surfaces.
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Affiliation(s)
- Gonzalo García
- Departamento de Química Física, Universidad de La Laguna, 38071, Spain
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Bolzán A, Schilardi P, Piatti R, Iwasita T, Cuesta A, Gutiérrez C, Arvia A. Comparative voltammetric and FTIRRAS study on the electro-oxidation of thiourea and methyl-thioureas on platinum in aqueous acid solutions. J Electroanal Chem (Lausanne) 2004. [DOI: 10.1016/j.jelechem.2004.04.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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In situ FTIRRAS study of the electro-oxidation reactions of thiourea and gold in aqueous acid solutions. J Electroanal Chem (Lausanne) 2003. [DOI: 10.1016/s0022-0728(03)00050-0] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Bolzán A, Piatti R, Arvia A. Electrochemical processes at gold∣thiourea-containing aqueous acid solution interfaces. J Electroanal Chem (Lausanne) 2003. [DOI: 10.1016/s0022-0728(03)00020-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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de Leon PFJ, Albano EV, Salvarezza RC, Solari HG. Interface dynamics for copper electrodeposition: the role of organic additives in the growth mode. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2002; 66:042601. [PMID: 12443238 DOI: 10.1103/physreve.66.042601] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2001] [Revised: 08/01/2002] [Indexed: 05/24/2023]
Abstract
An atomistic model for Cu electrodeposition under nonequilibrium conditions is presented. Cu electrodeposition takes place with a height-dependent deposition rate that accounts for fluctuations in the local Cu2+ ions concentration at the interface, followed by surface diffusion. This model leads to an unstable interface with the development of protrusions and grooves. Subsequently the model is extended to account for the presence of organic additives, which compete with Cu2+ for adsorption at protrusions, leading to a stable interface with scaling exponents consistent with those of the Edwards-Wilkinson equation. The model reproduces the interface evolution experimentally observed for Cu electrodeposition in the absence and in the presence of organic additives.
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Affiliation(s)
- Pablo F J de Leon
- Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas (INIFTA), UNLP, CONICET, Casilla de Correo 16, Sucursal 4, (1900) La Plata, Argentina
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Brunetti V, Blum B, Salvarezza RC, Arvia AJ, Schilardi PL, Cuesta A, Gayone JE, Zampieri G. Scanning Tunneling Microscopy, Fourier Transform Infrared Reflection−Absorption Spectroscopy, and X-ray Photoelectron Spectroscopy of Thiourea Adsorption from Aqueous Solutions on Silver (111). J Phys Chem B 2002. [DOI: 10.1021/jp0209695] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Gassa L, Lambi J, Bolzán A, Arvia A. Electrochemical impedance spectroscopy of thiourea electro-oxidation on copper electrodes in aqueous 0.5 M sulphuric acid. J Electroanal Chem (Lausanne) 2002. [DOI: 10.1016/s0022-0728(02)00829-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Bolzán A, Wakenge I, Piatti R, Salvarezza R, Arvia A. The behaviour of copper anodes in aqueous thiourea-containing sulphuric acid solutions. Open circuit potentials and electrochemical kinetics. J Electroanal Chem (Lausanne) 2001. [DOI: 10.1016/s0022-0728(00)00535-0] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Bolzán A, Haseeb A, Schilardi P, Piatti R, Salvarezza R, Arvia A. Anodisation of copper in thiourea- and formamidine disulphide-containing acid solution. J Electroanal Chem (Lausanne) 2001. [DOI: 10.1016/s0022-0728(00)00217-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Haseeb A, Schilardi P, Bolzan A, Piatti R, Salvarezza R, Arvia A. Anodisation of copper in thiourea-containing acid solution. J Electroanal Chem (Lausanne) 2001. [DOI: 10.1016/s0022-0728(00)00216-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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